uniq list from two lists

uniq_list_from_2_lists.js

/**
 * 
 * finds stings from list2 that are not included in list1 
 *
 */
 
const list1 = '123,234,566'.split(',').map(x => x.trim());
const list2 = '123,234,566, 756, 877'.split(',').map(x => x.trim());

const results = list2.filter(x => list1.indexOf(x) === -1).join(',');
console.log(results);